Refactoring. Pull up readMessage()

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1519453 13f79535-47bb-0310-9956-ffa450edef68
Researched the TODOs from the review of the AJP code against the list of actions.

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1519456 13f79535-47bb-0310-9956-ffa450edef68